the Hindu or Buddhist doctrine that person may be reborn successively into one of five classes of living beings (god or human or animal or hungry ghost or denizen of hell) depending on the person's own actions

a second or new birth

embodiment in a new form (especially the reappearance or a person in another form); "his reincarnation as a lion"

acceleration of a chemical reaction induced the presence of material that is chemically unchanged at the end of the reaction; "of the top 50 commodity chemicals, 30 are created directly by catalysis and another 6 are made from raw materials that are catalytically produced"